In the description of the speakers' morphological competence, one of the most well-known problems is that there are frequently ambiguous limits on the possibility of constructing (and understanding) new complex words. Chapter 2 demonstrated, for example, that un- can be freely attached to most adjectives but not all adjectives, that un- happens with nouns but only with a small number of nouns, and that un- can occur with verbs but not with all
86 verbs. A more difficult task awaits the analyst, who must devise a word-formation rule that produces (only) the correct set of complicated terms. Frequently, word-formation principles that appear clear and appropriate at first glance turn out to be troublesome following additional examination and consideration.
This is exemplified by the attachment of the nominalizing suffix - ity to adjectival bases ending in -ous, which is attested with forms such as curious - curiosity, capacious - capacity, and monstrous - monstrosity, among others.
However, the suffix -ity cannot be appended to all bases of this type, as indicated by the impossibility of the words glorious -
*gloriosity and furious - *furiosity, which are both examples of the word. What is the root cause of this restriction in -ity's ability to produce results?
Yet another common difficulty with many proposed word formation rules is that they are sometimes written in such a way that they explicitly forbid word forms that have been attested in the literature. Example: It is commonly considered that person nouns ending in -ee (such as employee and nominee) can only be formed with verbs that take an object ('employ someone' and 'nominate somebody, respectively), also known as transitive verbs. A nominee is someone who has been nominated, and an employee is someone who is employed. These -ee derivatives specify the object of the underlying verb, i.e. an employee is 'someone who is employed', and so on. However, even intransitive verbs (for example, escape - escapee, stand - standee) and even nouns (for
87 example, festschrift – festschriftee 'someone to whom a festschrift is devoted') can acquire the suffix –ee. In an ideal world, one would be able to come up with an explanation for these seemingly bizarre factors affecting the output of these affixes (Plag, 2002).
According to intuition, every discussion of productivity must include references to the speaker's ability to produce new words as well as the constraints imposed by the language system on the formation of new words. Thus, we get at a fundamental distinction in morphology: the distinction between words that are considered to be conceivable (or potential) and those that are considered to be real (or actual).
It is possible to define a feasible, or potential, word as one whose semantic, morphological, or phonological structure is consistent with the rules and regularities of the language. These norms and regularities must be expressed as clearly as possible before a particular form may be assigned the status of 'possible word.' It is also undeniable that the position of a word as a possibility is uncontroversial in the vast majority of cases. For example, it appears that the suffix –able can be attached to any transitive verb to make it into an adjectival adjective. As a result, affordable, readable, and manageable are all words that can be used. Of particular note is that these forms are also semantically transparent, which means that their meaning can be predicted based on the word-formation procedure that was followed when they were constructed. As a result, predictability of meaning is another characteristic of possible words.
88 In the case of the potential words affordable, readable, manageable, these words are also actual words, because they have already been coined and used by speakers. However, not all conceivable words are already in use, as demonstrated by the fact that, to return to the -able suffix, English speakers have not created -able derivatives on the basis of every transitive verb in the language. For example, neither the Oxford English Dictionary nor any other source I checked lists cannibalizable. As a result, this word does not exist in the sense that it is used by English speakers, and it is not a new word. The word is, nonetheless, a possible word in the English language since it conforms to the laws of English word creation, and if speakers could find a practical application for it, they would be delighted to employ it.
After we have established the meaning of the term "potential word," we may move on to the subject of what an actual (or existing) word is. A simple description would be to say that actual words are those that are now in use, which is a broad definition. In practice, though, when can we consider a word to be "in use"? It implies that some speaker has observed it being used in a certain context. Or is it simply that the vast majority of those working in the speech community are familiar with it? Or the fact that it is included in dictionaries? One of the issues is that there is a great deal of diversity between individual speakers. Not all terms that one speaker knows are likewise known by other speakers, i.e., a speaker's mental lexicon is never totally identical to the mental lexicon of any other speaker.
89 More to the point, it's not always clear whether we can say that a specific word is 'known' by an individual speaker, or that it has been "listed" in her mental lexicon. For example, we know that the more frequently a word appears in our vocabulary, the easier it is for us to memorize it and recall it later from our lexicon. This implies, however, that 'knowing of a word' is a gradual concept, and that we are more familiar with some terms than others as a result. Remember that this is also the fundamental assumption in foreign language learning, where a distinction is frequently drawn between what is referred to as "active" and "passive" vocabulary to facilitate learning. The active vocabulary, on the other hand, is made up of terms that we are more familiar with than the words that make up our passive vocabulary. The same contrast can be drawn between native speakers and non-native speakers, who both actively utilize just a subset of the terms with which they are conversant. The fact that even as native speakers, we frequently merely know that we have heard or read a given term before but do not know what it means is another example of graded knowledge of words.
Once again, while there may be some variation in individual differences between speakers and the concept of a certain term, it appears that there is a significant overlap in vocabulary between the individual native speakers of a language. It is because of this overlap that it is feasible to speak of a "vocabulary of the English language," even though this is an abstraction from the mental lexicons of the speakers in a strict sense. So that we can arrive at a
90 manageable definition of a "actual word," we can say that if we find an unambiguously documented word in a text or spoken by another speaker in a conversation, and there are other speakers of the language who can understand this word, we can say with some confidence that it is an actual word. As is obvious, both morphologically simple and complex words can be found in the class of actual words, and among the complex words, we find several that behave in accordance with the current norms of English word-formation. However, many actual words do not behave following these criteria, as we will see below. As an example, the words affordable ('can be afforded'), readable ('can be (easily) read'), and manageable ('can be managed') are all actual words that follow the word-formation rule for -able words, which states that - able derivatives have the meaning 'can be Xed', whereas knowledgeable (*'able to be knowledged') and probable (*'able to be probed') are actual words that do not follow the rule. The fundamental distinction between real and possible words is that only actual words can be idiosyncratic, that is, they cannot be formed in line with the norms of English word creation, but possible words can never be idiosyncratic.
We have examined the distinction between actual and possible words, and we can now shift our attention to the mechanisms that enable speakers to generate new possible words.
As we've already mentioned, the subject of how words are kept in the mental lexicon is one that deserves further discussion. This topic will be discussed in further depth in the following section
91 because it has significant implications for the nature of word- formation rules as well as their productivity.